Recently, so-called regenerative medicine, taking out a part of human body such as cells and tissues of skin, cartilage, bone, blood vessel, and organs, cultivating outside the body, and using in treatment of the same subject or a different patient, is developed and partly put in use. In such regenerative medicine, a small amount of cells sampled from human body is cultivated outside the body, and in such cell cultivation, it is most important to prevent contamination of cultured cells. In particular, when cultivating cells of plural subjects simultaneously, it is an important problem how to prevent from cross contamination, such as getting mixed in with cells of other subjects during incubation, or infectious bacteria, virus or mycoplasma etc. sticking to the cells.
On the other hand, for practical application of regenerative medicine, safe and inexpensive cell culture is demanded, and necessity is being discussed about automatic apparatus for operating the steps of incubation, culture medium exchange, and subculture until end of cell cultivation repeatedly and automatically. For automating such cultivation operation, in order to avoid the problem of cross contamination, at the present, one cell cultivation apparatus is used exclusively until the completion of cell cultivation for one subject, or the cultivation apparatus is used under incomplete contamination countermeasures using downflow air stream, but the problems are not solved sufficiently.
That is, when using one cell cultivation apparatus exclusively for one subject, cells of other subjects do not exist in the apparatus, and there is no problem of cross contamination during cultivation. However, the cost is higher from the viewpoint of efficiency of use of apparatus. In the cultivation apparatus using downflow air stream, cells of other subjects may exist in the apparatus, and contamination of containers for other subjects with such cells, bacteria, virus or mycoplasma cannot be prevented completely, and these are not sufficient countermeasures of problems of cross contamination.
To solve these problems, an apparatus has been developed for cultivating cells of plural subjects while preventing cross contamination (see International Publication No. 2004/011593 pamphlet FIG. 2). This automatic cultivation apparatus comprises a plurality of incubator units, and an operation unit commonly used for culture operation such as culture medium exchange and subculture. After end of culture operation of one subject, the apparatus is sterilized by ozone or other gas, but if the residual gas exists in the apparatus, the cells to be incubated may be destroyed. This automatic cultivation apparatus can sterilize the incubator units and the operation unit in the apparatus main body, but cannot sterilize the storage units storing reagents and culture tools used in cultivation, or the inlet-outlet unit for bringing in and out the reagents and culture tools. Therefore, cross contamination cannot be prevented completely including the storage units and the inlet-outlet unit.
The present invention is devised to solve the problems of the related art, and it is hence an object of the invention to present an automatic cell cultivation apparatus capable of sterilizing completely including the storage units and the inlet-outlet unit, without causing cross contamination, if used in cell cultivation of plural subjects.